(1) The ranks that may be held in a police force maintained under section 2 shall be such as may be prescribed by regulations under section 50 and the ranks so prescribed shall include, in addition to chief constable , deputy chief constable and assistant chief constable, the ranks of chief superintendent superintendent, chief inspector, inspector, sergeant and constable.
(2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
(3) Appointments and promotions to any rank below that of assistant chief constable in any police force maintained under section 2 shall be made, in accordance with regulations under section 50, by the chief constable.